1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method, and a program.
2. Description of the Related Art
When photographing a moving image with a video camera and the like, fluctuation may occur in the photographed image due to the influence of fluctuation of air. Such fluctuation of air is thought to occur when the index of refraction of light locally changes due to temperature difference and the like. When photographing a distant view using a telescopic lens, the light path becomes long as the distance from the subject to the video camera is large. Thus, when using the telescopic lens, the photographed image may be greatly influenced by the fluctuation of air and a noticeable fluctuation may appear in the photographed image. Specifically, in the image subjected to the influence of fluctuation, part of the subject that is originally linear appears undulating or a portion that appears distorted may be contained.
Such influence of fluctuation appears as a phenomenon in which the coordinate position of each pixel configuring the image varies within a local region. Thus, the influence of fluctuation can be removed by correcting the coordinate position of each pixel in the image. For instance, the influence of fluctuation with respect to the stationary subject can be easily removed by combining a filtering process such as an averaging process and a median process. However, the image degrades if the filtering process is performed on the moving subject rather than removing the influence of fluctuation. With regards to such issue, Japanese Patent Application Laid-Open No. 2008-160733 discloses a technique of detecting the moving subject using a dynamic body detecting technique, and performing the filtering process only on the stationary subject. Through the use of such technique, the filtering process will not be performed on an image region of the moving subject, and degradation of the image by such filtering process can be prevented.